An improved smoothed particle hydrodynamics method for the coupled simulation of fixed net structures in currents and waves

In the present paper, a numerical model, named smoothed particle hydrodynamics (SPH)-net model, is proposed for the coupled simulation of fixed net structures in currents and waves based on the coupling between the SPH method and screen model. The fluid is solved by the SPH method and the net structures are handled by the screen model, both of which are represented by a number of Lagrangian particles. A coupling algorithm between the SPH method and screen model is derived based on the momentum disturbance, which allows for accurate simulation of interactions between net structures and fluid. Thanks to the quasi-static assumption of the screen model, the proposed model can both handle the net structures in currents and waves. To validate the SPH-net model, numerical simulations were conducted on three distinct cases: fixed net panels in currents, a fixed net cage in currents, and a fixed net panel in the regular wave. The comparison of hydrodynamic forces on the net between the numerical results and experimental data demonstrates that the proposed SPH-net model has accuracy and reliability in predicting the hydrodynamic forces acting on fixed net structures in currents and regular waves.